Location-based services typically rely on location updates received for corresponding users from location-aware devices (e.g., mobile phones equipped with Global Positioning System (GPS) receivers) of the users. One issue with such systems is that the users may sometimes forget to carry their location-aware devices or mobile devices of the users may be turned off intentionally or inadvertently. In these situations, the location-based services do not have knowledge of, at least accurate knowledge of, the locations of the users, which results in undesirable results. Another issue is that location-based services are typically starved for data upon initial launch of the location-based services. Specifically, when a new location-based service initially launches, the new location-based service may not yet have a sufficient number of users to provide meaningful results.